Adsorption of acrolein, propanal, and allyl alcohol on Pd(111): a combined infrared reflection–absorption spectroscopy and temperature programmed desorption study

Atomistic-level understanding of the interaction of α,β-unsaturated aldehydes and their derivatives with late transition metals is of fundamental importance for the rational design of new catalytic materials with the desired selectivity towards C=C vs. C=O bond partial hydrogenation. In this study, we investigate the interaction of acrolein, and its partial hydrogenation products propanal and allyl alcohol, with Pd(111) as a prototypical system. A combination of infrared reflection–absorption spectroscopy (IRAS) and temperature programmed desorption (TPD) experiments was applied under well-defined ultrahigh vacuum (UHV) conditions to obtain detailed information on the adsorption geometries of acrolein, propanal, and allyl alcohol as a function of coverage. We compare the IR spectra obtained for multilayer coverages, reflecting the molecular structure of unperturbed molecules, with the spectra acquired for sub-monolayer coverages, at which the chemical bonds of the molecules are strongly distorted. Coverage-dependent IR spectra of acrolein on Pd(111) point to the strong changes in the adsorption geometry with increasing acrolein coverage. Acrolein adsorbs with the C=C and C=O bonds lying parallel to the surface in the low coverage regime and changes its geometry to a more upright orientation with increasing coverage. TPD studies indicate decomposition of the species adsorbed in the sub-monolayer regime upon heating. Similar strong coverage dependence of the IR spectra were found for propanal and allyl alcohol. For all investigated molecules a detailed assignment of vibrational bands is reported

Tourism management and information and communication technologies (ICTs): The new smart destinations approach

Este artículo analiza el nuevo enfoque de los destinos inteligentes para la gestión turística a escala local. Se estudia su génesis y se realiza una propuesta de conceptualización desde una perspectiva sistémica, que se contrasta con la gestión turística actual mediante una encuesta a municipios turísticos de la Comunidad Valenciana. Los resultados ponen de relieve que no se ha asumido como objetivo de gestión el enfoque de los destinos inteligentes, el cual requiere un proyecto global que incorpore cinco ámbitos fundamentales: gobernanza, sostenibilidad, conectividad, sistema de información e innovación. No obstante, la complejidad asociada a este enfoque hace aconsejable un desarrollo de tipo flexible, escalable y adaptado a cada entorno territorial.Aquest article analitza la nova perspectiva de les destinacions intel·ligents per a la gestió turística a escala local. Se n’hi estudia la gènesi i s’hi realitza una proposta de conceptualització des d’un punt de vista sistèmic que es contrasta amb la gestió turística actual mitjançant una enquesta als municipis turístics de la Comunitat Valenciana. Els resultats demostren que no s’ha assumit com a objectiu de gestió la perspectiva de les destinacions intel·ligents, la qual requereix un projecte global que integre cinc àmbits fonamentals: governança, sostenibilitat, connectivitat, sistema d’informació i innovació. Tanmateix, la complexitat associada a aquesta perspectiva fa aconsellable un desenvolupament de tipus flexible, escalable i adaptat a cada entorn territorial.This article analyzes the new smart destinations approach to tourism management at the local level. We examine the origins of this approach and propose a conceptualization from a systemic perspective, which is contrasted with current tourism management strategies through a survey of tourist destinations in the Valencia Region. The results show that the smart destinations approach has not been considered as a management objective. This approach requires a global project incorporating five key areas: governance, sustainability, connectivity, information system and innovation. However, due to the complexity of the smart tourist destination approach, a particular kind of development that is flexible, scalable and adapted to each geographical environment is recommendable.El presente trabajo se enmarca en el proyecto de investigación Nuevos enfoques para la planificación y gestión del territorio turístico: Conceptualización, análisis de experiencias y problemas. Definición de modelos operativos para destinos turísticos inteligentes (CSO2014-59193-R), financiado por el Programa Estatal de I+D+i, Ministerio de Economía y Competitividad

On solving large-scale multistage stochastic problems with a new specialized interior-point approach

A novel approach based on a specialized interior-point method (IPM) is presented for solving large-scale stochastic multistage continuous optimization problems, which represent the uncertainty in strategic multistage and operational two-stage scenario trees, the latter being rooted at the strategic nodes. This new solution approach considers a split-variable formulation of the strategic and operational structures, for which copies are made of the strategic nodes and the structures are rooted in the form of nested strategic-operational two-stage trees. The specialized IPM solves the normal equations of the problem’s Newton system by combining Cholesky factorizations with preconditioned conjugate gradients, doing so for, respectively, the constraints of the stochastic formulation and those that equate the split-variables. We show that, for multistage stochastic problems, the preconditioner (i) is a block-diagonal matrix composed of as many shifted tridiagonal matrices as the number of nested strategicoperational two-stage trees, thus allowing the efficient solution of systems of equations; (ii) its complexity in a multistage stochastic problem is equivalent to that of a very large-scale two-stage problem. A broad computational experience is reported for large multistage stochastic supply network design (SND) and revenue management (RM) problems; the mathematical structures vary greatly for those two application types. Some of the most difficult instances of SND had 5 stages, 839 million variables, 13 million quadratic variables, 21 million constraints, and 3750 scenario tree nodes; while those of RM had 8 stages, 278 million variables, 100 million constraints, and 100,000 scenario tree nodes. For those problems, the proposed approach obtained the solution in 2.3 days using 167 gigabytes of memory for SND, and in 1.7 days using 83 gigabytes for RM; while the state-of-the-art solver CPLEX v20.1 required more than 24 days and 526 gigabytes for SND, and more than 19 days and 410 gigabytes for RMPeer ReviewedPreprin

On solving large-scale multistage stochastic optimization problems with a new specialized interior-point approach

© 2023 The Authors. Published by Elsevier B.VA novel approach based on a specialized interior-point method (IPM) is presented for solving largescale stochastic multistage continuous optimization problems, which represent the uncertainty in strategic multistage and operational two-stage scenario trees. This new solution approach considers a splitvariable formulation of the strategic and operational structures. The specialized IPM solves the normal equations by combining Cholesky factorizations with preconditioned conjugate gradients, doing so for, respectively, the constraints of the stochastic formulation and those that equate the split-variables. We show that, for multistage stochastic problems, the preconditioner (i) is a block-diagonal matrix composed of as many shifted tridiagonal matrices as the number of nested strategic-operational two-stage trees, thus allowing the efficient solution of systems of equations; (ii) its complexity in a multistage stochastic problem is equivalent to that of a very large-scale two-stage problem. A broad computational experience is reported for large multistage stochastic supply network design (SND) and revenue management (RM) problems. Some of the most difficult instances of SND had 5 stages, 839 million linear variables, 13 million quadratic variables, 21 million constraints, and 3750 scenario tree nodes; while those of RM had 8 stages, 278 million linear variables, 100 million constraints, and 100,000 scenario tree nodes. For those problems, the proposed approach obtained the solution in 1.1 days using 174 gigabytes of memory for SND, and in 1.7 days using 83 gigabytes for RM; while CPLEX v20.1 required more than 53 days and 531 gigabytes for SND, and more than 19 days and 410 gigabytes for RM.J. Castro was supported by the MCIN/AEI/FEDER grant RTI2018-097580-B-I00. L.E. Escudero was supported by the MCIN/AEI/10.13039/501100011033 grant PID2021-122640OB-I00. J.F. Monge was supported by the MCIN/AEI/10.13039/501100011033/ERDF grants PID2019-105952GB-I00 and PID2021-122344NB-I00, and by PROMETEO/2021/063 grant funded by the government of the Valencia Community, Spain.Peer ReviewedPostprint (published version

Crowd Monitoring in Smart Destinations Based on GDPR-Ready Opportunistic RF Scanning and Classification of WiFi Devices to Identify and Classify Visitors’ Origins

Crowd monitoring was an essential measure to deal with over-tourism problems in urban destinations in the pre-COVID era. It will play a crucial role in the pandemic scenario when restarting tourism and making destinations safer. Notably, a Destination Management Organisation (DMO) of a smart destination needs to deploy a technological layer for crowd monitoring that allows data gathering in order to count visitors and distinguish them from residents. The correct identification of visitors versus residents by a DMO, while privacy rights (e.g., Regulation EU 2016/679, also known as GDPR) are ensured, is an ongoing problem that has not been fully solved. In this paper, we describe a novel approach to gathering crowd data by processing (i) massive scanning of WiFi access points of the smart destination to find SSIDs (Service Set Identifier), as well as (ii) the exposed Preferred Network List (PNL) containing the SSIDs of WiFi access points to which WiFi-enabled mobile devices are likely to connect. These data enable us to provide the number of visitors and residents of a crowd at a given point of interest of a tourism destination. A pilot study has been conducted in the city of Alcoi (Spain), comparing data from our approach with data provided by manually filled surveys from the Alcoi Tourist Info office, with an average accuracy of 83%, thus showing the feasibility of our policy to enrich the information system of a smart destination.This research was carried out within the research Project Alcoi Tourist Lab framework, co-funded by the Alcoi City Council & the Valencian Innovation Agency. The research was also partially funded by project UAPOSTCOVID19-10 from the University of Alicante. Finally, this research was partly supported by the EU CEF project GreenMov, CARM HORECOV-21 project (https://horecovid.com/ (accessed on 12 January 2022)). is financed through the Call for Public Aid destined to finance the Strategic projects contemplated in the Research and Innovation Strategy for Smart Specialization - RIS3MUR Strategy by the Autonomous Community of the Region of Murcia, through the Ministry of Economic Development, Tourism and Employment within the framework of the FEDER Region of Murcia Operational Program 2014–2020 within the framework Thematic Objective 1. Strengthen research, technological development and innovation by 80% and with CARM’s own funds in 20%, and finally the EU project H2020 NIoVE (833742)

Isolation of high quality graphene from Ru by solution phase intercalation

2013 AIP Publishing LL

Alloy oxidation as a route to chemically active nanocomposites of gold atoms in a reducible oxide matrix

While nanoparticles are being pursued actively for a number of applications, dispersed atomic species have been explored far less in functional materials architectures, primarily because composites comprising dispersed atoms are challenging to synthesize and difficult to stabilize against sintering or coarsening. Here we show that room temperature oxidation of Au–Sn alloys produces nanostructures whose surface is terminated by a reducible amorphous oxide that contains atomically dispersed Au. Analysis of the oxidation process shows that the dispersal of Au in the oxide can be explained by predominant oxygen anion diffusion and kinetically limitedmetalmass transport, which restrict phase separation due to a preferential oxidation of Sn. Nanostructures prepared by oxidation of nanoscale Au–Sn alloys with intermediate Au content (30–50%) show high activity in a CO-oxidation probe reaction due to a cooperative mechanism involving Au atoms as sites for CO adsorption and reaction to CO2 embedded in a reducible oxide that serves as a renewable oxygen reservoir. Our results demonstrate a reliable approach toward nanocomposites involving oxide-embedded, atomically dispersed noble metal species

Alloy oxidation as a route to chemically active nanocomposites of gold atoms in a reducible oxide matrix

While nanoparticles are being pursued actively for a number of applications, dispersed atomic species have been explored far less in functional materials architectures, primarily because composites comprising dispersed atoms are challenging to synthesize and difficult to stabilize against sintering or coarsening. Here we show that room temperature oxidation of Au–Sn alloys produces nanostructures whose surface is terminated by a reducible amorphous oxide that contains atomically dispersed Au. Analysis of the oxidation process shows that the dispersal of Au in the oxide can be explained by predominant oxygen anion diffusion and kinetically limitedmetalmass transport, which restrict phase separation due to a preferential oxidation of Sn. Nanostructures prepared by oxidation of nanoscale Au–Sn alloys with intermediate Au content (30–50%) show high activity in a CO-oxidation probe reaction due to a cooperative mechanism involving Au atoms as sites for CO adsorption and reaction to CO2 embedded in a reducible oxide that serves as a renewable oxygen reservoir. Our results demonstrate a reliable approach toward nanocomposites involving oxide-embedded, atomically dispersed noble metal species

Molecular and biological characterization of an isolate of Tomato mottle mosaic virus (ToMMV) infecting tomato and other experimental hosts in eastern Spain

[EN] Tomato is known to be a natural and experimental reservoir host for many plant viruses. In the last few years a new tobamovirus species, Tomato mottle mosaic virus (ToMMV), has been described infecting tomato and pepper plants in several countries worldwide. Upon observation of symptoms in tomato plants growing in a greenhouse in Valencia, Spain, we aimed to ascertain the etiology of the disease. Using standard molecular techniques, we first detected a positive sense single-stranded RNA virus as the probable causal agent. Next, we amplified and sequenced its full-length genomic RNA which identified the virus as a new ToMMV isolate. Through extensive assays on distinct plant species, we investigated the host range of the Spanish ToMMV isolate. Several plant species were locally and/or systemically infected by the virus, some of which had not been previously reported as ToMMV hosts despite they are commonly used in research greenhouses. Finally, two reliable molecular diagnostic techniques were developed and used to assess the presence of ToMMV. This is the first observation of ToMMV in tomato plants in Europe. We discuss the possibility that, given the high sequence homology between ToMMV and Tomato mosaic virus, the former may have been mistakenly diagnosed as the latter by serological methods.This work was supported by grants BFU2015-70261-P and BFU2015-65037-P (to C.H. and S.F.E., respectively) from Spain Ministry of Economy, Industry and Competitiveness/FEDER.Ambros Palaguerri, S.; Martinez, F.; Ivars, P.; Hernandez Fort, C.; De La Iglesia Jordán, F.; Elena Fito, SF. (2017). Molecular and biological characterization of an isolate of Tomato mottle mosaic virus (ToMMV) infecting tomato and other experimental hosts in eastern Spain. European Journal of Plant Pathology. 149(2):261-268. https://doi.org/10.1007/s10658-017-1180-2S2612681492Fillmer, K., Adkins, S., Pongam, P., & D’Ella, T. (2015). Complete genome sequence of a Tomato mottle mosaic virus isolated from the United States. Genome Announcements, 3(2), e00167–e00115.Hadas, R., Pearlsman, M., Gefen, T., Lachman, O., Hadar, E., Sharabany, G., et al. (2004). Indexing system for Tomato mosaic virus (ToMV) in commercial tomato seed lots. Phytoparasitica, 32(4), 421–424.Lewandowski, D. J., & Dawson, W. O. (1998). Tobamoviruses. In A. Granoff & R. G. Webster (Eds.), Encyclopedia of virology (Vol. 3, 2nd ed., pp. 1780–1783). New York: Academic Press Inc..Li, R., Gao, S., Fel, Z., & Ling, K. (2013). Complete genome sequence of a new Tobamovirus naturally infecting tomatoes in Mexico. Genome Announcements, 1(5), e00794–e00713.Li, Y. Y., Wang, C. L., Xiang, D., Li, R. H., Liu, Y., & Li, F. (2014). First report of Tomato mottle mosaic virus infection of pepper in China. Plant Disease, 98(10), 1447.Martin, D. P., Murrell, B., Golden, M., Khoosal, A., Muhire, B. (2015). RDP4: detection and analysis of recombination patterns in virus genomes. Virus Evolution, 1(1), vev003.Moreira, S. R., Eiras, M., Chaves, A. L. R., Galleti, S. R., & Colariccio, A. (2003). Characterição de uma nova estirpe do Tomato mosaic virus isolada de tomateiro no estado de São Paulo. Fitopatologia Brasileira, 28(6), 602–607.Padmanabhan, C., Zheng, Y., Li, R., Martin, G. B., Fei, Z., & Ling, K. S. (2015). Complete genome sequence of a tomato-infecting Tomato mottle mosaic virus in New York. Genome Announcements, 3(6), e01523–e01515.Pirovano, W., Boetzer, M., Miozzi, L., & Pantaleo, V. (2015). Bioinformatics approaches for viral metagenomics in plants using short RNAs: Model case of study and application to a Cicer arietinum population. Frontiers in Microbiology, 5, 790.Ruiz-Ruiz, S., Moreno, P., Guerri, J., & Ambrós, S. (2006). The complete nucleotide sequence of a severe stem pitting isolate of Citrus tristeza virus from Spain: Comparison with isolates from different origins. Archives of Virology, 151(2), 387398.Salem, N., Mansour, A., Ciuffo, M., Falk, B. W., & Turina, M. (2016). A new tobamovirus infecting tomato crops in Jordan. Archives of Virology, 161(2), 503–506.Soler, S., Prohens, J., López, C., Aramburu, J., Galipienso, L., & Nuez, F. (2010). Viruses infecting tomato in València, Spain: Occurrence, distribution and effect of seed origin. Journal of Phytopathology, 158(11–12), 797–805.Tamura, L., Stecher, G., Peterson, D., Filipski, A., & Kumar, S. (2013). MEGA6: Molecular evolutionary genetics analysis version 6.0. Molecular Biology and Evolution, 30(12), 2725–2729.Turina, M., Geraats, B. P. J., & Ciuffo, M. (2016). First report of Tomato mottle mosaic virus in tomato crops in Israel. New Disease Reports, 33, 1.Webster, C. G., Rosskopf, E. N., Lucas, L., Mellinger, H. C., & Adkins, S. (2014). First report of Tomato mottle mosaic virus infecting tomato in the United States. Plant Health Progress. doi: 10.1094/PHP-BR-14-0023